Questioning The Discrimination On The Tejon

[Don in SoCal]

I need a little help here in understanding the primary discrimination knob.  Here is my observation.  8X9 coil, Using a lead pellet as a test target, buried 3", when placed in All Metal the target sounds off loud and clear. When switched to the discriminate mode, knob far left (zero discrim,) I don't receive any signal. I would think that at the lowest discriminate setting I should be getting a signal from iron on up. Is it possible the internal discriminate circuit out of adjustment?

[Noah (FL)]

The Tejon has two disc circuits.   Do they both have the same results on the test target?   If they both react the same then they are probably not out of adjustment and it’s just the difference in depth between the all metal and discrimination circuits.  If the two discriminators give different results on the target then they may need adjusted. Most Tesoros have a small trimmer pot on the pcb to fine tune the discriminators. I haven’t had a Tejon opened up myself but I’m sure a photo of the pcb can be found online with a little google detective work.   Also depending  on the size of the lead bb/pellet 3” may be pushing it depth wise.  Let us know how it goes. 

[Don in SoCal]

I do believe I checked the targets in both the primary and secondary disc. circuits and got the same results, I will do a retest.  The pellets were equal in size and buried at 1", 2", 3", and 4".  With my Lobo LST and the same coil I could hit all targets in All Metal, switch to Discriminate and in the lowest disc. setting I could get an easy  repeatable signal from the 1, 2. and 3 " targets.  I expected the same performance from the Tejon but  in disc. setting I didn't get a response from any of the targets. 

[Mark Gillespie]

This is how I used my Tejon.  Each site would be a little different but the principle stays the same.

My main discrimination would be set to knock out most of the iron at this particular site.  Then since I've always been a nickel man I would set the discrimination to just pop and crack on a buried nickel.  Now you might be wondering why in the world I would hunt that way?  Since most, I mean the majority of gold rings belong to women and most are thinner, they will read at or well below a nickel.  

While hunting with this setup I'd often switch to the second discrimination to see if the target would be at or below a nickel.  Always dug those signals and found a lot of rings.  The audio on the Tesoro machines are, in my opinion far superior to other detectors, well maybe not but the fact is we have to rely on the audio report more with a machine that lacks a display.  I really loved my Tejon and also the Vaquero.

[kac]

I run mine similar but use 2nd disc for quick range check to id stuff in the alum/nickel and gold and everything else. So.. first disc set at line below nickel which will pick up on beavertails but cut majority of foil out. Nickels have a robust sound but have a roll to them. Gold rings have more roll to the audio and aluminum square tabs and larger can slaw have a flat sound. Tiny signals that carry longer are most likely aluminum.

2nd disc I set to tab which scrubs on the ring tabs. Folded ring tabs may sound off and are worth digging as they come in the same as flying eagle cents. Badly degraded zinc pennies will break. Copper pennies come in loud and clean and silver will have a softer roll.

Alternatively hunting in areas with high iron I set the first disc at iron but not to lose the iron. Any silver in the area that may be masked normally will sound in loud and clear. You may get a broken signal in one direction but clean on another is a good indicator of iron masking an object. 2nd disc I will set to break on any additional trash such as can slaw. This setup worked well for me in older areas that have deeper targets.

All metal mode may be louder or softer depending on the object your detecting when comparing to the disc modes. In other words you may get a little pop on an object in disc and a longer tone in AM. Ground conditions and GB can effect that as well as for instance a larger or longer piece of aluminum you may normally have it trimmed out but not fully so the pop can be the thicker part of the object picking up.

I use AM to check not only for pin pointing but determining the objects size and depth. Disc modes just keep things quiet until I get a hit worthy of investigating. A buried can you probably already know carries the sound much further so lifting the coil off will help too. Lifting coil on small low conductor hits does the same as can slaw will carry the signal more than a small piece of gold. IE a bracelet will have a very short range when compared to a foil wrapper.

Both Disc should be spot on with the object. Easy way is to set them to break on one then check to the other.

[Monte]

On ‎1‎/‎23‎/‎2020 at 11:06 PM, osbod007 said:

I do believe I checked the targets in both the primary and secondary disc. circuits and got the same results, I will do a retest.  The pellets were equal in size and buried at 1", 2", 3", and 4".  With my Lobo LST and the same coil I could hit all targets in All Metal, switch to Discriminate and in the lowest disc. setting I could get an easy  repeatable signal from the 1, 2. and 3 " targets.  I expected the same performance from the Tejon but  in disc. setting I didn't get a response from any of the targets. 

Getting to understand Tesoro's, or any make and model detector, and differences in the terminology and design and unction can take some time.  Especially if you really want to get to know them well.  Here, you're talking about the Tejón  and Lobo SuperTRAQ.  What they have in common is that they were made by the same manufacturer and they share the same search coils.  What they have different, among other things, is they were from different design engineers and used different Discrimination circuitry ranges, and also different Ground Balance designs for their two search modes:  Threshold-based All Metal and silent-search motion Discrimination.

The Lobo SuperTRAQ was design by Dave Johnson and the two modes are independent of each other  The true All Metal mode relies on an auto-tracking GB, while the silent-search Disc. mode Ground Balance is preset internally.  Also, Dave's Discrimination design is what Tesoro calls an ED-180 of All Metal Accept setting that is very sensitive and reactive to all ferrous-range targets at the minimum Disc. setting.  So much so that it can even be reactive to the ground mineral make-up and require a lower-end Disc. setting to quiet it down.

The Tejón was designed by Jack Gifford, and the variable GB control for the threshold-based All Metal mode is also utilized by the silent-search Discriminate circuitry.  But keep in mind that most Tesoro models have a somewhat positive off-set from the All Metal mode's GB.  That means that is the All Metal mode have a spot-on GB, the Disc. mode's GB reference is going to be a bit positive.  If you adjust the GB in the silent-search Disc. mode for peak performance, or what would be close to 'spot-on', then the All Metal / Pinpoint mode's GB is going to be somewhat negative.  Generally it is still very useable due to the auto-tune in the All Metal mode

If the GB is set too positive, that can have a  negative impact on the detection ability of the Discriminate mode, and since I hunt in the Disc. mode most of the tie, I prefer to have the best Disc. mode GB.  Therefore, I will adjust to very slightly negative in All Metal and double-check in the Disc. mode to make sure I am not too negative such that there is falsing when I bob the search coil over dirt.

Then we get to the Discriminate mode adjustment range and we note two things:

1.. There is no separate selector, such as a toggle switch, to select the conventional All Metal mode and it is a 'clicked' access at the fully counter-clockwise end of the primary Disc. control.  The Disc. control and Alt. Disc. control are both matching in what their adjustment ranges should be, and w note that at the fully counter-clockwise setting, both of these are labeled 'All Metal.'  That implies they are using the full-range ED-180 Discriminate Range of acceptance, but from testing I did very early on, and a Discussion with Jack about the Disc. ranges used on several different models,  it is very close to accepting all ferrous and non-ferrous targets, but maybe not quite a full-range of acceptance.

2.. The Tejón is a good responder to coin-size targets throughout the range of acceptance, but the reactivity or responsiveness to tiny-sized targets such as very small gold nuggets or lead BB's /shot is not on the same level as that of some other detectors .... to include their own Lobo SuperTRAQ.  I don't believe the Tejón Disc. adjusts as low as the Lobo ST.

Simply two different detectors and circuitry designs, thus different in-the-field results.

Monte

 

 

[Rivers rat]

22 minutes ago, Monte said:

Getting to understand Tesoro's, or any make and model detector, and differences in the terminology and design and unction can take some time.  Especially if you really want to get to know them well.  Here, you're talking about the Tejón  and Lobo SuperTRAQ.  What they have in common is that they were made by the same manufacturer and they share the same search coils.  What they have different, among other things, is they were from different design engineers and used different Discrimination circuitry ranges, and also different Ground Balance designs for their two search modes:  Threshold-based All Metal and silent-search motion Discrimination.

The Lobo SuperTRAQ was design by Dave Johnson and the two modes are independent of each other  The true All Metal mode relies on an auto-tracking GB, while the silent-search Disc. mode Ground Balance is preset internally.  Also, Dave's Discrimination design is what Tesoro calls an ED-180 of All Metal Accept setting that is very sensitive and reactive to all ferrous-range targets at the minimum Disc. setting.  So much so that it can even be reactive to the ground mineral make-up and require a lower-end Disc. setting to quiet it down.

The Tejón was designed by Jack Gifford, and the variable GB control for the threshold-based All Metal mode is also utilized by the silent-search Discriminate circuitry.  But keep in mind that most Tesoro models have a somewhat positive off-set from the All Metal mode's GB.  That means that is the All Metal mode have a spot-on GB, the Disc. mode's GB reference is going to be a bit positive.  If you adjust the GB in the silent-search Disc. mode for peak performance, or what would be close to 'spot-on', then the All Metal / Pinpoint mode's GB is going to be somewhat negative.  Generally it is still very useable due to the auto-tune in the All Metal mode

If the GB is set too positive, that can have a  negative impact on the detection ability of the Discriminate mode, and since I hunt in the Disc. mode most of the tie, I prefer to have the best Disc. mode GB.  Therefore, I will adjust to very slightly negative in All Metal and double-check in the Disc. mode to make sure I am not too negative such that there is falsing when I bob the search coil over dirt.

Then we get to the Discriminate mode adjustment range and we note two things:

1.. There is no separate selector, such as a toggle switch, to select the conventional All Metal mode and it is a 'clicked' access at the fully counter-clockwise end of the primary Disc. control.  The Disc. control and Alt. Disc. control are both matching in what their adjustment ranges should be, and w note that at the fully counter-clockwise setting, both of these are labeled 'All Metal.'  That implies they are using the full-range ED-180 Discriminate Range of acceptance, but from testing I did very early on, and a Discussion with Jack about the Disc. ranges used on several different models,  it is very close to accepting all ferrous and non-ferrous targets, but maybe not quite a full-range of acceptance.

2.. The Tejón is a good responder to coin-size targets throughout the range of acceptance, but the reactivity or responsiveness to tiny-sized targets such as very small gold nuggets or lead BB's /shot is not on the same level as that of some other detectors .... to include their own Lobo SuperTRAQ.  I don't believe the Tejón Disc. adjusts as low as the Lobo ST.

Simply two different detectors and circuitry designs, thus different in-the-field results.

Monte

 

 

Spot on Monte :0 the Tejon paired with the 5.75DD has found me more gold on the River than most of my machine........i pick up deep stuff wit this coil in the field too(but too small for vast sites) the DD is 5.75 is for me the number one ex aequo coil with the very rare tiny elliptical un iron infested area ,mounted on my LOBO it is an absolute delight and i focus on nails carpet and still find stuff.If only Tesoro had built a Lobo ST UMAX......

 

RR

[Monte]

21 minutes ago, Rivers rat said:

If only Tesoro had built a Lobo ST UMAX......

RR

RR, that would have been nice, and they almost did.  Dave Johnson made the Lobo SuperTRAQ and the microMAX (µMAX) Diablo.  The Diablo was Dave's favorite gold nugget detector design and I really enjoyed hunting with it.  Never could figure out why Tesoro discontinued it after such a short period of time.  Likely because it lacked a Discriminate mode.

I would have liked the Lobo ST even in the Tejón's physical design.  Of the two models, I enjoyed the Lobo SuperTRAQ more, and had no practical use for the dual-Disc. of the Tejón.  An attempt to compete with the Fisher 1200 series .... about the time Fisher realized it wasn't so good and got away from it.  But if they could-have done an LST in a µMAX package, it sure would have made the longer-day hunts a lot more enjoyable and comfortable.

Monte